Broad-band optical communications typically require high data rate optoelectronic transceivers incorporating an optical receiver capable of converting high data rate signals from optical to electrical domain and an optical transmitter capable of converting high data rate signals from electrical to optical domain. An optoelectronic transceiver may include an optical transmitter (Tx) circuit and an optical receiver (Rx) circuit, which may be implemented with one or more photonic chips, which may be mounted on a circuit board with driver and signal processing electronics. An optical Tx circuit may include an electro-optic (EO) converter, typically an optical modulator such as a waveguide Mach Zehnder modulator (MZM) for devices operating in the GHz frequency range and beyond. An optical Rx circuit may include one or more optical couplers and/or optical mixers and may further include one or more opto-electric (OE) converters, such as one or more photodetectors, for example in the form of PIN photodiodes.
High-data-rate optoelectronic transceiver modules may require device-specific precise optimization of various parameters of the transmitter and the receiver. These parameters may include, for example, skew-compensation values of the RF channels of the transmitter and of the receiver, filter settings for digital pre-compensation of bandwidth limitations of the hardware, and/or channel power level adjustment, e.g. for squareness correction of quadrature amplitude modulated signals, and alike. In particular higher-order modulation formats, for example 16QAM and 64QAM, and high symbol rates, for example 60 GBaud, require highly optimized transceiver settings, such as precise skew compensation values. However, module settings that are found during factory calibration under laboratory conditions may not match optimal settings in the field. The need for module calibration in the field further increases with the rise of new transceiver platforms that separate the digital electrical data processing unit from an analogue electro-optic conversion engine. For example CFP2-ACO hot-pluggable optical transceiver modules may be hosted in the field on printed circuit boards (PCB) that are sourced separately from the pluggables. Consequently, the digital host unit and the analogue pluggable optical transceiver are calibrated in their respective factory independently, and their optimal settings may not match. However calibration of conventional transceiver modules typically requires on-site technical personal and thus may be too costly to perform in the field.